By continuing to use this site you consent to the use of cookies on your device as described in our
Cookie Policy unless you have disabled them. You can change your Cookie Settings at any time but parts of our site will not function correctly without them.

Rudra said the move was aimed at identifying pollution sources which can be fine-tuned as per priority to ensure an ambient air quality.

The WBPCB had 48 air monitoring stations all over the state in 2011, a senior official said adding the state-run pollution control body had increased the number substantially to bring all the zones under its network.

Rubbishing allegations that almost all the air monitoring stations of WBPCB were either outdated or defunct, Rudra said that among the 17 monitoring stations in the city, 15 are being operated manually while two are automated. One of the two stations is under renovation and is expected to be functional in a month.

To a query about reports of lack of devices equipped to measure PM 2.5, the WBPCB chief said among the air monitoring stations, four can measure PM 2.5 (particulate matter 2.5) while the rest can measure PM 10 (particulate matter 10).

Particles less than 2.5 PM (micrometres) are called PM 2.5. They are approximately 1/30th of the average width of human hair and is generally described as fine particles. PM 10 on the other hand is particulate matter 10 micrometres or less in diametre, an official explained.

On reports about air quality level having reached critical levels in the city, he said air quality is also governed by meteorological factors on which not much can be done during extreme weather conditions.

"Kolkata is certainly not among the top polluted cities in the world," he said.

Rudra said the WBPCB has collaborated with National Environment Engineering Research Institute to figure out the source of pollutants in Kolkata Metropolitan Area as part of the effort to create an ambient environment for the citizens.

Recently, the draft of National Clean Air Programme (NCAP) came out with a list of 100 "non-attainment cities" not having met the requisite air quality standards which included Kolkata.